He has a bent wrist. In a V grip you can get the rod pretty close to flat without bending your wrist. If you get your thumb in the way and don't bend your wrist you can't get it back past 2 oclock. So I am going to go out on a limb here and make the assumption Lefty also said don't bend your wrist.

Turbineblade, you can also disregard the don't bend your wrist thing when you are better.